1) Team Speak for team voice meetings
2) Skype for one on one IM on the days we don't have team meetings.
3) Email for communication that needs to be documented
4) Trello/Cohuman/Wunderkit for PM/task management depending on the project style.
5) SVM for versioning/document/asset storage
6) Dropbox for backup of above files
7) Group Forums for a general hangout.

We've been using Fisheye for source history (shows commit messages, can create rss feeds for commits, view project history across multiple branches, and lots of other stuff) and Crucible for code reviews.

Jira + Greenhopper is a great tool for agile planning, and bug/issue tracking.

MediaWiki is a good free tool for a general purpose scratch pad, I use it to store url links, and non-source documentation (high level overviews, checklists for adding new subprojects / adding files / checking out and building source).

Microsoft SharePoint is a great multipurpose tool if you can afford the license + SQL Server + the time to administer it. Only really useful to larger organizations.

I would go with IRC for meetings, there exists pretty good bots to manage the meetings. Github private or public repositories for source control, bug tracker and wiki. Skype for fast one on one discussions. FTP server for sharing documents and other files.

(1) IRC for mostly-immediate-mode conversations and format meetings
(2) email for non-time-sensitive and formal conversations
(3) mumble, skype, and google for voice/video chats
(4) VCS for code and assets (officially we use bzr, except for certain teams who work with git upstreams)
(5) google docs for sharing documents (google docs needs a lot of work to become scalable)
(6) various third-party software for planning (kanban boards, etc)
(7) various wikis for, I dunno, stuff that no one can ever find and rarely gets updated but is quick to write so you can say "I put it on the wiki"

Pretty much all that technology is client-agnostic (except mumble and skype) and it's all freely available.